EEC guideline requirements for data loggers
| Requirement | What it means in practice |
|---|---|
| Technically suitable for the task and environment | the instrument's operating range covers the conditions of the cold room, freezer or warehouse; the housing withstands humidity and frost |
| Reliable time-stamped recording | synchronizable clock, protection against accidental stop of recording |
| Measurement range | covers the expected minimum and maximum with a margin |
| Interval from 1 to 15 minutes or longer | 5–10 min for a warehouse, 1–5 min for cold rooms and vehicles |
| Sufficient memory | capacity = duration / interval; one week at 5 min is 2,016 readings |
| Verification or calibration | valid on the mapping date, with details stated in the report |
| Accuracy no worse than ±0.5 °C | within the range of the acceptance criteria, not just at +20 °C |
| Data transfer to the system | export of raw data without manual recalculation |
The guideline also recommends using data loggers of a single type for a single mapping study and choosing models with a status indicator, so that during placement it is clear the instrument is recording.
Example: the Smartag recording temperature indicators we manufacture are listed in the Federal Register of Approved Measuring Instruments under No. 91745-24. Temperature accuracy is ±0.5 °C in the range −30…+40 °C; the verification interval is 2 years, or 1 year for versions with humidity measurement. Verification of a specific instrument is checked in FSIS Arshin using this register number and the serial number.
Verification in Russia
Monitoring the storage conditions of medicinal products falls within the scope of state regulation of ensuring the uniformity of measurements. Therefore, mapping and monitoring use measuring instruments of an approved type that are listed in the Federal Information Fund for Ensuring the Uniformity of Measurements and have passed verification. The storage rules in Order No. 260n explicitly refer to verified instruments for recording temperature and humidity.
Since 2020, verification has been confirmed by a record of its results in FSIS Arshin; a paper certificate or verification mark is issued additionally. Before mapping, check the following for each data logger by its serial number:
- that the measuring instrument type is approved and its type approval certificate has not expired;
- that verification is valid for all dates of the study;
- that verification covers the required range and channels (temperature, humidity, external probe);
- that the result is “fit for use”.
Verification and calibration are not the same. Verification confirms compliance with metrological requirements and is mandatory within the scope of state regulation. Calibration determines the actual error values and is useful for internal purposes, such as assessing drift between verifications.
How to choose a data logger
For warehouses
Standalone temperature or temperature/humidity loggers with memory for at least 2–3 weeks at a 5-minute interval, rack mounting and an operation indicator. To compare seasons, it is convenient to use the same fleet of instruments.
For cold rooms and vehicles
Low-inertia sensors, an interval of down to 1 minute, resistance to condensation. For vehicles, a ruggedized housing and secure mounting.
For freezers and ultra-low temperatures
Data loggers with external probes (thermocouples, Pt100/Pt1000), where the instrument's operating temperature is higher than the probe's. Lithium batteries are checked for frost resistance.
For continuous monitoring
Sensors with data transmission, buffering on loss of communication, battery monitoring and the ability to swap a module during verification without interrupting monitoring.
Checks before placement
- Match serial numbers against the placement table and verification records.
- Synchronize the time of all instruments with a single source.
- Set the same interval and a delayed start.
- Check that battery charge will last the entire study with a margin.
- Perform an intercomparison: keep the instruments together for 1–2 hours in a stable environment and record any discrepancies.
Frequently asked questions
What data logger accuracy is required for mapping?
The EEC guideline sets an absolute error of no more than ±0.5 °C within the acceptance criteria of the object under study.
Is verification of loggers mandatory for mapping?
Yes. A data logger must have a verification mark and/or verification certificate valid at the time of mapping, or a calibration record where this is provided for by law. In Russia, verified measuring instruments are used to monitor the storage conditions of medicinal products.
How do I check a data logger's verification?
Find the record by type and serial number in FSIS Arshin and make sure the verification is valid for the study dates and covers the required range.
Can different logger models be mixed?
The EEC guideline recommends using data loggers of a single type for a single mapping study so that the results are consistent.
How much memory does a data logger need?
Divide the study duration by the logging interval and add a margin. For 7 days at a 5-minute interval, that is 2,016 readings per channel; if humidity is also measured, the same again.